I also just had to revet back to 6.6.7.  It really makes no sense it would be a USB drive issue seeing that 6.6.7 boots just fine and so do 6.7.0, it is just that the server has limited access.  For example, I found it interesting I could update my dockers, but the dockers themselves could not reach the Internet.  So this seems to be a Docker integration issue.    I am kind of surprised that we have not heard anything from unRAID on this nor has a 6.7.1 come out to fix it as it yet. (U